/Engine/Plugins/Experimental/ChaosVehiclesPlugin/Source/ChaosVehicles/Public/ChaosVehicleMovementComponent.h
Set the user input for handbrake
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="Game|Components|ChaosVehicleMovement") void SetHandbrakeInput ( bool bNewHandbrake )